[pups] RL and RK Last Cylinder Warning (RE: VTServer)

Something I thought is worth warning folks about. For RL01, RL02, RK06 and RK07 (at least), the last cylinder is RESERVED for bad blocks and the pack serial number. Except for maintaining the bad block list, software should not write there, and should at least preserve the serial number (and its mirror copies that are usually present) when doing so. The current implementation of VTServer (in particular, the code in the "hk" driver in pdpvtstand) does not appear to take that into account. The problem is that if you take a *full* pack image from a pack and then restore that *full* pack image to a different pack, you will wipe out the latter's bad block info (and perhaps write in some areas that are known not to be very good). Traditionally, Unix variants dealt with this by insisting that you use error free (Suffix -EF in the DEC part number on the pack) disk packs. However, if you are using real hardware you may no longer have those available. Just a "heads up". (PS: FYI I am currently working on a flavor of the "vt" driver that will work over a DR11C. With the proper cabling (it takes different cables for input and output) you can manage over 1MB per minute that way -- about 20 times faster than a serial port. The code is pretty simple and should work on any old "plain jane" parallel port. (I do not know how it would behave on a modern serial port)). I had this working a long time ago, and VTServer prompted me to dredge it up again and test it. It still works with my PIII 350 under Win98 (it is old DOS code that accesses the old style parallel port directly). Within a few weeks I expect to provide a "pt" device driver for pdpvtstand, and cabling information and some source code for the PC side (which would be an example only). The protocol as I currently use it has no checksum. However I plan to modify "copy" to provide that information so that the results can be checked after the transfer. Jay Jaeger --- Jay R. Jaeger The Computer Collection cube1(a)home.com visit http://members.home.net/thecomputercollection Received: (from major@localhost) by minnie.cs.adfa.edu.au (8.9.3/8.9.3) id NAA27320 for pups-liszt; Wed, 4 Apr 2001 13:11:21 +1000 (EST) (envelope-from owner-pups(a)minnie.cs.adfa.edu.au) Received: from henry.cs.adfa.edu.au (henry.cs.adfa.edu.au [131.236.21.158]) by minnie.cs.adfa.edu.au (8.9.3/8.9.3) with ESMTP id NAA27316 for &lt;pups(a)minnie.cs.adfa.edu.au&gt;au>; Wed, 4 Apr 2001 13:11:19 +1000 (EST) (envelope-from wkt(a)henry.cs.adfa.edu.au) Received: (from wkt@localhost) by henry.cs.adfa.edu.au (8.11.2/8.9.3) id f3434A010297; Wed, 4 Apr 2001 13:04:10 +1000 (EST) (envelope-from wkt) From: Warren Toomey &lt;wkt(a)henry.cs.adfa.edu.au&gt; Message-Id: &lt;200104040304.f3434A010297(a)henry.cs.adfa.edu.au&gt; Subject: [pups] Re: RL and RK Last Cylinder Warning (RE: VTServer) In-Reply-To: <4.3.2.7.2.20010403213011.044d3da0@cirithi> from Jay Jaeger at "Apr 3, 2001 09:40:08 pm" To: Jay Jaeger &lt;cube1(a)home.com&gt; Date: Wed, 4 Apr 2001 13:04:10 +1000 (EST) CC: PDP-11 Unix Preservation Society &lt;pups(a)minnie.cs.adfa.edu.au&gt; Reply-To: wkt(a)cs.adfa.edu.au X-Mailer: ELM [version 2.4ME+ PL68 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-pups(a)minnie.cs.adfa.edu.au Precedence: bulk In article by Jay Jaeger: Jay, I've added your warnings to the new version, vtserver2.3a-20010404.tar.gz, which I just put out a few seconds ago. This also contains a patch to the ODT download code from Charles H Dickman &lt;chd_1(a)nktelco.net&gt;et>: I made some changes to the source to wait for the current memory value and trailing space to be echoed by ODT. I also had a bit of trouble if the output values were not padded with 0's. I think this is because any character other than a valid octal digit or a return or a ctrl-j is illegal in that context and causes an error. ftp://minnie.cs.adfa.edu.au/pub/PDP-11/Vtserver/vtserver2.3a-20010404.tar.gz Jay, if you could write a ptboot.s bootstrapper and a pt.c driver which speaks the same protocol [should be easy - just use vt.c and rewrite vtgetc() and vtputc()], then I'll happily add it to the next version. Cheers, Warren Received: (from major@localhost) by minnie.cs.adfa.edu.au (8.9.3/8.9.3) id KAA33889 for pups-liszt; Thu, 5 Apr 2001 10:11:17 +1000 (EST) (envelope-from owner-pups(a)minnie.cs.adfa.edu.au) Received: from henry.cs.adfa.edu.au (henry.cs.adfa.edu.au [131.236.21.158]) by minnie.cs.adfa.edu.au (8.9.3/8.9.3) with ESMTP id KAA33880; Thu, 5 Apr 2001 10:11:13 +1000 (EST) (envelope-from wkt(a)henry.cs.adfa.edu.au) Received: (from wkt@localhost) by henry.cs.adfa.edu.au (8.11.2/8.9.3) id f35042G12856; Thu, 5 Apr 2001 10:04:02 +1000 (EST) (envelope-from wkt) From: Warren Toomey &lt;wkt(a)henry.cs.adfa.edu.au&gt; Message-Id: &lt;200104050004.f35042G12856(a)henry.cs.adfa.edu.au&gt; Subject: [pups] Ancient Unix licenses? (fwd) To: PDP-11 Unix Preservation Society &lt;pups(a)minnie.cs.adfa.edu.au&gt;au>, The Unix Heritage Society &lt;tuhs(a)minnie.cs.adfa.edu.au&gt; Date: Thu, 5 Apr 2001 10:04:02 +1000 (EST) Reply-To: wkt(a)cs.adfa.edu.au X-Mailer: ELM [version 2.4ME+ PL68 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-pups(a)minnie.cs.adfa.edu.au Precedence: bulk All, I've received this e-mail from a student at NYU Law Department. If any of you have copies of old Unix licenses, and your organisation would be prepared to release copies to Greg, could you contact him. Also, if you could send me copies of your licenses, that would be great too. About 8 people have already done this, and I am happy to act as a repository for this old information. Cheers, Warren ----- Forwarded message from gmp216(a)nyu.edu ----- From gmp(a)zebware.com Thu Apr 5 09:49:39 2001 To: wkt(a)cs.adfa.edu.au From: gmp216(a)nyu.edu Subject: Ancient Unix licenses? Date: Wed, 04 Apr 2001 23:49:31 +0000 Sender: gmp(a)zebware.com Peter Salus identified you as the collector of old Unix versions, so I thought you might be able to help me with a project I am working on. I am studying the legal history of Unix for a colloquium at NYU, and I would really love to see copies of the old Unix licenses that the various universities signed. Do you happen to have access to any of these? All I can find are the transcribed tape labels from your archive which say things like "subject to the software agreement you have with Western Electric." Thanks! And thank you also for pushing to make the source code available. That has been an immeasurable help. --- Greg Pomerantz NYU Law, J.D. '02 ----- End of forwarded message from gmp216(a)nyu.edu ----- Received: (from major@localhost) by minnie.cs.adfa.edu.au (8.9.3/8.9.3) id SAA36569 for pups-liszt; Thu, 5 Apr 2001 18:36:58 +1000 (EST) (envelope-from owner-pups(a)minnie.cs.adfa.edu.au)